In the case of devices such as HVAC, shop equipment, candy or beverage dispensers, the control is realized by means of of embedded electronics.
Because the number of devices produced is higher than about 100 per year, the cost price of an embedded control system is much more favourable than with a standard PLC.
In terms of price, it is advantageous to place Power Supplies, Relays, Transmitter Modules and Modems for e.g. GSM/LTE on the PCB.
Sometimes special sensors are needed, for which separate electronics have to be made.
This also applies to actuators such as ventilators or servo motors which require a servo control or frequency converter.
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